diff --git a/envs/phoronix-test-suite/shell.nix b/envs/phoronix-test-suite/shell.nix
index 8b97e9e..9beface 100644
--- a/envs/phoronix-test-suite/shell.nix
+++ b/envs/phoronix-test-suite/shell.nix
@@ -10,7 +10,6 @@ pkgs.stdenv.mkDerivation {
     popt
     libaio
     perl
-    gcc7
     pcre
     glibc.out
     glibc.static
diff --git a/envs/yocto/shell.nix b/envs/yocto/shell.nix
index c0aab5e..8a292b6 100644
--- a/envs/yocto/shell.nix
+++ b/envs/yocto/shell.nix
@@ -1,5 +1,6 @@
 { pkgs ? import <nixpkgs> { }
 , extraPkgs ? [ ]
+, extraPythonPkgs ? [ ]
 }:
 
 let
@@ -43,7 +44,7 @@ let
       (ncurses'.override { unicodeSupport = false; })
       patch
       perl
-      (python3.withPackages (ps: [ ps.setuptools ps.pyaml ]))
+      (python3.withPackages (ps: [ ps.setuptools ps.pyaml ] ++ extraPythonPkgs))
       rpcsvc-proto
       unzip
       util-linux